If you look closely this photo shows how Spark's plumage is changing as he matures. His wing is still brown, the color of a sub-adult falcon. But the feathers on his back--which used to be brown--have been replaced with blue "adult" feathers. Interesting to see him change before our eyes! By next nesting season all the brown feathers will be gone and he will bear the typical blue/gray coloration of a mature adult.
Meanwhile, the eggs appear to be deteriorating. It looks like at least one and maybe two have/are "melting" into the gravel as they decompose. My guess is they were again infertile this year but without examining them we won't know for sure.
Additional updates will be posted throughout the summer if/when anything notable occurs.